<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        .box{
            width: 3000px;
            height: 3000px;
            overflow: auto;
            background-color: #f2f2f2;
            background-image: url(../../../mask.png), url(../../../demo.jpg);
            background-repeat: space round;
            /* background-attachment: fixed; */
        }
    </style>
</head>
<body>
    <div class="box"></div>
</body>
</html>